Unusual Core 2 Duo temperatures

My core 2 duo e6600 is idling at 65 C according to the bios. I turned it off and left it off overnight. I power it on this morning and it starts at 30 C (which is deffinitally hotter than my room temp) and climbs from there to 65 in minutes, with no load at all.

I'm using stock cooling, in a thermaltake Armor case (with the 250mm fan).

Taking it off and putting it back on will make the problem worse if you don't re-apply some Arctic Silver 5. If you move it around at all after you install it you will break the thermal bond created by the thermal pad, and you will need to replace it.

You can take it off and put it on again without adding more thermal material. With it off you can see how well it made contact and then spread it out more even. The push pins can be difficult to use. When you put the HSF on make sure they all are up all the way and then set their bases completely in the holes then push them down until they click. It should take some pressure. If the pins are already down and you try to push them through it will take a extreme amount of force and possibly break something. Once it's on try lifting from each corner to confirm it's attached. With the mobo out of the case you can see if the pins attached properly by looking at the bottom.